1860 Silver 1 Baht Coin Of Rama 4 Siam, Counterfeit?

I recently came across this coin on ebay and as an avid collector of siamese coins was interested in placing a bid until I compared it to one I already have, I contacted the seller who seemed very vague and asked my opinion of the coin,I told him that in my opinion it was a fake as the design was incorrect, one of the signs was the chakra wheel on the reverse had 12 arms instead of the usual 9, it just didn't seem right.It was a couple of days later when I noticed that it had sold for £310, could anybody out there please confirm my suspicions, I've been collecting 40 years since my late father introduced me to the hobby but I am still learning everyday. The first two images are of a legit coin and the second two are of the one I believe to be a copy.